Method of and apparatus for managing disc defects using temporary defect management information (TDFL) and temporary defect management information (TDDS), and disc having the TDFL and TDDS

ABSTRACT

A disc having an updatable defect management area used by an apparatus for managing defects on the disc, the disc including a user data area which includes user data, a spare area that is a substitute area for a defect existing in the user data area, and an area in which are recorded an address of data that is last recorded in the user data area and an address of a replacement data recorded in the spare area. Accordingly, the disc defect management method and apparatus are applicable to a recordable disc such as a write-once disc while effectively using a defect management area of the disc.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.11/045,149, filed Jan. 31, 2005, currently pending, which is acontinuation of U.S. patent application Ser. No. 10/670,363, filed Sep.26, 2003, currently pending, which claims the benefit of Korean PatentApplication No. 2002-63850, filed on Oct. 18, 2002 in the KoreanIntellectual Property Office, and Korean Patent Application No.2002-79755 filed on Dec. 13, 2002 in the Korean Intellectual PropertyOffice, the disclosures of which are incorporated herein in theirentirety by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to disc defect management, and moreparticularly, to a method of and apparatus for managing defects thereinusing a temporary defect management area (TDMA) and a disc having theTDMA for managing defects thereon.

2. Description of the Related Art

Disc defect management is the process of rewriting data stored in a userdata area of a disc, in which a defect exists, to a new portion of thedisc's data area, thereby compensating for a data loss otherwise causedby the defect. In general, disc defect management is performed using alinear replacement method or a slipping replacement method. In thelinear replacement method, the user data area in which a defect existsis replaced with a spare data area having no defects. In the slippingreplacement method, the user data area with the defect is slipped andthe next user data area having no defects is used.

Both the linear replacement method and the slipping replacement are,however, applicable only to rewritable discs, such as a DVD-RAM/RW, onwhich data can be repeatedly recorded and recording can be performedusing a random access method. In other words, the linear replacement andslipping replacement methods are difficult to apply to a write-oncediscs, on which recording is allowed only once.

In general, the presence of defects in a disc is detected by recordingthe data on the disc, and confirming whether data has been recordedcorrectly on the disc. However, once data is recorded on a write-oncedisc, it is impossible to overwrite new data and manage defects therein.

After the development of a CD-R and a DVD-R, a high-density write-oncedisc with a recording capacity of several dozen GBs was introduced. Thistype of disc can be used as a backup disc since it is not expensive andallows random access so as to enable fast reading operations. However,since disc defect management is not available for write-once discs, abackup operation may be discontinued when a defective area (i.e., anarea where a defect exists) is detected during the backup operation. Inaddition, since a backup operation is generally performed when a systemis not frequently used (e.g., at night when a system manager does notoperate the system), it is more likely that the backup operation will bestopped and remain discontinued because a defective area of a write-oncedisc is detected.

SUMMARY OF THE INVENTION

The present invention provides a write-once disc on which defects aremanaged, and a disc defect management method and apparatus usable withthe write-once disc.

The present invention also provides a write-once disc on which defectsare managed and a disc defect management method and apparatus that canmanage disc defects on the disc even when a defect is detected during arecording operation, allowing the recording operation to be performedwithout interruption.

Additional aspects and/or advantages of the invention will be set forthin part in the description which follows and, in part, will be obviousfrom the description, or may be learned by practice of the invention.

According to an aspect of the present invention, a disc includes a userdata area in which user data is recorded; a spare area that includes asubstitute area in which is recorded replacement data for a portion ofthe user data recorded in a defective area existing in the user dataarea; and an area in which there are recorded an address of data that islast recorded in the user data area and an address of replacement datarecorded in the spare area.

According to an aspect, the disc further includes a temporary defectmanagement area that includes temporary defect information and temporarydefect management information recorded each recording operation so as tobe used for disc defect management, wherein the temporary defectmanagement area is an area that includes the address of the data lastrecorded in the user data area and the address of the replacement datarecorded in the spare area.

According to another aspect of the present invention, a method ofmanaging a defect in a disc includes recording user data in a user dataarea; again recording user data, which is recorded in a defective areaof the user data area in which a defect exists, in a spare area of thedisc so as to make replacement data for a portion of the user datarecorded in the defective area; and recording an address of data, whichis last recorded in the user data area, and an address of thereplacement data, which is recorded in the spare area, in a temporarydefect management area that is formed to perform disc defect management.

According to another aspect of the present invention, a recording and/orreproducing apparatus includes a recording/reading unit that recordsdata on or reads data from a disc; and a controller that controls therecording/reading unit to record user data in a user data area of thedisc; controls the recording/reading unit to again record a portion ofthe user data recorded in a defective area of the user data area asreplacement data in a spare area; and controls the recording/readingunit to record an address of data, which is last recorded in the userdata area, and an address of the replacement data, which is lastrecorded in the spare area, in a temporary defect management area thatis formed to perform disc defect management.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and/or other aspects and advantages of the present inventionwill become more apparent by describing in detail embodiments thereofwith reference to the accompanying drawings in which:

FIG. 1 is a block diagram of a recording apparatus according to anembodiment of the present invention;

FIGS. 2A and 2B illustrate structures of a disc according to embodimentsof the present invention;

FIG. 3A illustrates data structures of the disc of FIGS. 2A and 2Baccording to an embodiment of the present invention;

FIG. 3B illustrates a data structure of a disc with defect managementareas (DMAs) and a temporary DMA (TDMA) as shown in FIG. 3A;

FIGS. 4A through 4D illustrate data structures of a TDMA according toembodiments of the present invention;

FIG. 5A illustrates a data structure of temporary defect information(TDFL) #i according to an embodiment of the present invention;

FIG. 5B illustrates a data structure of temporary defect information(TDFL) #i according to another embodiment of the present invention;

FIG. 6 illustrates a data structure of temporary defect managementinformation (TDDS) #i according to an embodiment of the presentinvention;

FIG. 7 illustrates diagrams explaining recording of data in a user dataarea A and a spare area B, according to an embodiment of the presentinvention;

FIG. 8 is a diagram illustrating effective use of a data area accordingto an embodiment of the present invention;

FIGS. 9A and 9B illustrate data structures of TDFL #1 and TDFL #2recorded according to the recording of data shown in FIG. 7;

FIG. 10 illustrates a data structure of information regarding defect #i;

FIG. 11 is a flowchart illustrating a disc defect management methodaccording to an embodiment of the present invention; and

FIG. 12 is a flowchart illustrating a disc defect management methodaccording to another embodiment of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Reference will now be made in detail to the present embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings, wherein like reference numerals refer to the like elementsthroughout. The embodiments are described below in order to explain thepresent invention by referring to the figures.

FIG. 1 is a block diagram of a recording and/or reproducing apparatusaccording to an embodiment of the present invention. Referring to FIG.1, the recording and/or reproducing apparatus includes arecording/reading unit 1, a controller 2, and a memory 3. Therecording/reading unit 1 records data on a disc 100, which is aninformation storage medium according to an embodiment of the presentinvention, and reads back the data from the disc 100 to verify theaccuracy of the recorded data. The controller 2 performs disc defectmanagement according to an embodiment of the present invention.

In the shown embodiment, the controller 2 uses a verify-after-writemethod in which data is recorded on the disc 100 in predetermined unitsof data, and the accuracy of the recorded data is verified to detect ifan area of the disc 100 has a defect. In other words, the controller 2records user data on the disc 100 in units of recording operations, andverifies the recorded user data to detect an area of the disc 100 inwhich a defect exists. Thereafter, the controller 2 creates informationthat indicates the position of the area with the defect and stores thecreated information in the memory 3. When the amount of the storedinformation reaches a predetermined level or the verify-after-writeoperation is performed a predetermined number of times, the controller 2records the stored information as temporary defect information on thedisc 100.

According to an aspect of the invention, the recording operation is aunit of work determined according to a user's intention or is arecording work to be performed. According to the shown embodiment, arecording operation indicates a process in which the disc 100 is loadedinto the recording and/or reproducing apparatus, data is recorded on thedisc 100, and the disc 100 is taken out from the recording apparatus.However, it is understood that the recording operation can be otherwisedefined.

During the recording operation, the user data is recorded and verifiedat least once. In general, while not required, data is recorded andverified several times. Defect information, which is obtained using theverify-after-write method, is temporarily stored as temporary defectinformation in the memory 3. When a user presses the eject button (notshown) of the recording and/or reproducing apparatus in order to removethe disc 100 after recording of data, the controller 2 expects therecording operation to be terminated. The controller 2 reads theinformation from the memory 3, provides it to the recording/reading unit1, and controls the recording/reading unit 1 to record it on the disc100.

When the recording of data is completed (i.e., additional data will notbe recorded on the disc 100 and the disc 100 needs to be finalized), thecontroller 2 controls the recording/reading unit 1 to rewrite therecorded temporary defect information and temporary defect managementinformation to a defect management area (DMA) of the disc 100 as defectmanagement information.

During reproduction, the recording and/or reproducing apparatus utilizesthe defect information and the defect management information in thedefect management area and/or the temporary defect management area inorder to access the recorded user data. While described in terms of arecording and/or reproducing apparatus as shown in FIG. 1, it isunderstood that the apparatus can be an individual recording orreproducing apparatus or a recording and reproducing apparatus.

FIGS. 2A and 2B illustrate structures of the disc 100 of FIG. 1according to embodiments of the present invention. FIG. 2A illustratesin detail a single record layer disc representation of disc 100 having arecord layer L0. The disc 100 includes a lead-in area, a data area, anda lead-out area. The lead-in area is located in an inner part of thedisc 100 and the lead-out area is located in an outer part of the disc100. The data area is present between the lead-in area and the lead-outarea and divided into a user data area and a spare area.

The user data area is an area where user data is recorded. The sparearea is a replacement area for a user data area having a defect, servingto compensate for loss in the recording area due to the defect. On theassumption that defects may occur within the disc 100, it is preferable,but not required, that the spare area assumes about 5% of the entiredata capacity of the disc 100, so that a greater amount of data can berecorded on the disc 100.

FIG. 2B illustrates a double record layer disc representation of disc100 having two record layers L0 and L1. A lead-in area, a data area, andan outer area are sequentially formed from the inner part of the firstrecord layer L0 to its outer part. Also, an outer area, a data area, anda lead-out area are sequentially formed from the outer part of thesecond record layer L1 to its inner part. Unlike the single record layerdisc of FIG. 2A, the lead-out area is present at the second record layerL1 in the inner part of the disc 100 of FIG. 2B. That is, the disc 100of FIG. 2B has an opposite track path (OTP) in which data is recordedstarting from the lead-in area of the first record layer L0 toward theouter area of the first record layer L0 and continuing from the outerarea of the second record layer L1 to the lead-out area of the secondrecord layer L1. The spare area is allotted to each of the record layersL0 and L1 according to the shown embodiment, but need not be soallocated in all aspects of the invention.

In the shown embodiment, the spare areas are present between the userdata area and the lead-out area and between the user data area and theouter area. If necessary, a portion of the user data area may be used asanother spare area. That is, it is understood that more than one sparearea may be present between the lead-in area and the lead-out area.

FIG. 3A illustrates structures of the disc 100 of FIGS. 2A and 2B,according to an embodiment of the present invention. Referring to FIG.3A, if the disc 100 is a single record layer disc, at least one DMA ispresent in the lead-in area and the lead-out area of the disc 100.Further, at least one temporary defect management area (TDMA) is alsopresent in the lead-in area and the lead-out area. If the disc 100 is adouble record layer disc, at least one DMA is present in the lead-inarea, the lead-out area, and the outer area, and at least one TDMA ispresent in the lead-in area and the lead-out area. For the double recordlayer disc shown in FIG. 2B, the DMA and the TDMA are preferably formedin the lead-in area and the lead-out area, which are located in theinner part of the disc 100, respectively.

In general, the DMA includes information relating to managing discdefects in the disc 100. Such information includes the structure of thedisc 100 for disc defect management, the recording position of defectinformation, whether defect management is performed, and the positionand size of a spare area. For a write-once disc, when the aboveinformation changes, new data is recorded after previously recordeddata.

Also, when the disc 100 is loaded into a recording/reading apparatussuch as that shown in FIG. 1, the apparatus generally reads data from alead-in area and a lead-out area of the disc 100 to determine how tomanage the disc 100 and to record data on or read data from the disc100. However, if the amount of data recorded in the lead-in area and/orthe lead-out area increases, a longer time is spent on preparing therecording or reproducing of data after the loading of the disc 100.

To solve this problem and for other reasons, an aspect of the presentinvention uses temporary defect management information and temporarydefect information that are to be recorded in a TDMA. The TDMA isallotted to the lead-in area and/or the lead-out area of a disc, beingseparated from the DMA. That is, only the last recorded defectinformation and the last recorded defect management information, whichare required to perform disc defect management, are recorded in the DMA.As such, the amount of information that the recording/reading unitrequires for a recording/reproducing operation is reduced.

In the shown embodiment, since disc defect management is performed usingthe linear replacement method, the temporary defect information includesdefect position information indicating a position of an area of the disc100 having a defect and replacement position information indicating aposition of an area of the disc 100 on which is stored replacement data.The replacement data is data to replace a portion of the user datarecorded in a defective area of the user data area. While not required,it is preferable that the temporary defect information further includesinformation indicating whether the area having the defect is a singledefect block or a continuous defect block.

The temporary defect management information is used to manage thetemporary defect information and includes information indicating aposition of the disc 100 where the temporary defect information isrecorded. While not required, it is preferable that the temporary defectmanagement information further includes information indicating aposition of user data that is last recorded in the user data area and areplacement area that is last formed in a spare area. Detailed datastructures of temporary defect information and temporary defectmanagement information will be explained below.

In the shown embodiment, the temporary defect information and temporarydefect management information are recorded every time a recordingoperation ends. In the TDMA, information regarding a defect, whichoccurs in data recorded during recording operation #0, and informationregarding a replacement area are recorded as temporary defectinformation #0. Information regarding a defect, which occurs in datarecorded during recording operation #1, and information regarding areplacement area are recorded as temporary defect information #1.Further, information for managing temporary defect information #0, #1 isrecorded as temporary defect management information #0, #1 in the TDMA.When additional data cannot be recorded in the data area or a user doesnot wish to record additional data therein (i.e., the data needs to befinalized), temporary defect information recorded in a temporary defectinformation area and temporary defect management information recorded ina temporary defect management information area are rewritten to the DMA.

The temporary defect information and the temporary defect managementinformation are rewritten to the DMA for at least the following reason.Where additional data will not be recorded on the disc 100 (i.e., thedisc 100 needs to be finalized), only last recorded ones of thetemporary defect management information and temporary defectinformation, which have been updated several times, are again recordedin the DMA. Thus, the recording/reading unit 1 can read fast defectmanagement information from the disc 100 just by reading the lastrecorded defect management information, thereby enabling fastinitializing of the disc 100. Further, recording of the temporary defectinformation and temporary defect management information in the DMAincreases the reliability of information.

In the shown embodiment, defect information contained in previouslyrecorded temporary defect information #0, #1, #2 and #i−1 is furthercontained in temporary defect information #i. Thus, it is easy tofinalize the disc 100 just by reading defect information contained inlast recorded temporary defect information #i and to rewrite the readdefect information to the DMA.

In the case of a high-density disc with a recording capacity of severaldozens of GBs, it is desirable that a cluster is allocated to an area inwhich temporary defect management information #i is recorded, and fourto eight clusters are allocated to an area in which temporary defectinformation #i is recorded. This is because it is generally preferableto record new information in units of clusters to update informationwhen a minimum physical unit of record is a cluster, although the amountof temporary defect information #i is just several KBs. A total amountof defects allowed in a disc is preferably about 5 percent of the discrecording capacity. For instance, about four to eight clusters arerequired to record temporary defect information #i, considering thatinformation regarding a defect is about 8 bytes long and the size of acluster is 64 KBs long.

The verify-after-write method can also be performed on temporary defectinformation #i and temporary defect management information #i accordingto an aspect of the invention. When a defect is detected, informationrecorded in an area of a disc having a defect may be either recorded ina spare area using the linear replacement method, or recorded in an areaadjacent to the TDMA using the slipping replacement method.

FIG. 3B illustrates a data structure of the disc 100 with a TDMA andDMAs as shown in FIG. 3A. If the disc 100 is a single record layer asshown in FIG. 2A, the TDMA and the DMA are present in at least one of alead-in area and a lead-out area of the disc 100. If the disc is adouble record layer disc 100 as shown in FIG. 2B, the TDMA and the DMAare present in at least one of a lead-in area, a lead-out area, and anouter area. While not required, it is preferable that the TDMA and theDMA are present in the lead-in area and the lead-out area, respectively.

Referring to FIG. 3B, two DMAs are formed to increase the robustness ofdefect management information and defect information. In FIG. 3B, thedisc 100 includes a temporary defect management area (TDMA), a Test areain which recording conditions of data are measured, a Drive and Discinformation area in which information regarding a drive used during arecording and/or reproducing operation(s) and disc informationindicating whether a disc is a single record layer disc or a doublerecord layer are recorded, and Buffer 1, Buffer 2, and Buffer 3 areasthat act as buffers that indicate borders of the respective areas.

FIGS. 4A through 4D illustrate data structures of a TDMA according toembodiments of the present invention. Referring to FIG. 4A, a TDMA islogically divided into a temporary defect information area and atemporary defect management information area. In the shown embodiment ofthe temporary defect information area, temporary defect information TDFL#0, TDFL #1, TDFL #2 are sequentially recorded starting from a start ofthis area toward an end of the area. The temporary defect informationTDFL #0, TDFL #1, TDFL #2, . . . are repeatedly recorded several timesto increase the robustness of the information. In particular, FIG. 4Aillustrates recording of the temporary defect information TDFL #0 Ptimes.

In the temporary defect management information area, temporary defectmanagement information TDDS #0, TDDS #1, TDDS #2 are sequentiallyrecorded starting from a start of this area. The temporary defectmanagement information TDDS #0, TDDS #1, and TDDS #2 correspond to thetemporary defect information TDFL #0, TDFL #1, and TDFL #2,respectively.

Referring to the embodiment shown in FIG. 4B, as compared to FIG. 4A, aDMA is also logically divided into a temporary defect information areaand a temporary defect management information area, but the sequences ofrecording information are not the same as that shown in FIG. 4A. Morespecifically, in the temporary defect information area, temporary defectinformation TDFL #0, TDFL #1, TDFL #2 are sequentially recorded startingfrom an end of this area toward a start of this area. Similarly, thetemporary defect information TDFL #0, TDFL #1, TDFL #2 are repeatedlyrecorded several times to increase the robustness of information.

In particular, FIG. 4B illustrates an embodiment in which the temporarydefect information TDFL #0 is recorded P times. In the temporary defectmanagement information area, temporary defect management informationTDDS #0, TDDS #1, TDDS #2 is sequentially recorded starting from the endof this area. The temporary defect management information TDDS #0, TDDS#1, and TDDS #2 correspond to the defect information TDFL #0, TDFL #1,and TDFL #2, respectively.

Referring to FIG. 4C, corresponding temporary defect information andtemporary defect management information are recorded as pairs ofinformation in a TDMA. More specifically, temporary managementinformation TDMA #0, TDMA #1 are sequentially recorded starting from thestart of the TDMA. The temporary management information TDMA #0 containsa pair of corresponding temporary defect management TDDS #0 andtemporary defect information TDFL #0. Temporary management informationTDMA #1 contains a pair of corresponding temporary defect managementinformation TDDS #1 and temporary defect information TDFL #1. Thetemporary defect information TDFL #0, TDFL #1, TDFL #2 are repeatedlyrecorded several times to increase the robustness of the information. Inparticular, FIG. 4C illustrates recording of the temporary defectinformation TDFL #0 P times.

Referring to FIG. 4D, compared to the TDMA of FIG. 4C, correspondingtemporary defect information and temporary defect management informationare recorded as pairs of information in a TDMA, but the sequence ofrecording the information is not the same. More specifically, in theTDMA, temporary management information TDMA #0, TDMA #1 are sequentiallyrecorded starting from an end of the TDMA. The temporary managementinformation TDMA #0 contains a pair of corresponding temporary defectmanagement information TDDS #0 and temporary defect information TDFL #0.The temporary management information TDMA #1 contains a pair ofcorresponding temporary defect management information TDDS #1 andtemporary defect information TDFL #1. Similarly, the temporary defectinformation TDFL #0, TDFL #1, TDFL #2 are repeatedly recorded severaltimes to increase the robustness of information. In particular, FIG. 4Dillustrates recording of the temporary defect information TDFL #0 Ptimes.

FIGS. 5A and 5B illustrate data structures of temporary defectmanagement information TDDS #i. In detail, FIG. 5A illustrates a datastructure of temporary defect management information TDDS #i recorded ona single record layer disc 100 such as that shown in FIG. 2A. Thetemporary defect management information TDDS #i contains an identifierfor the temporary defect management information TDDS #i, and informationregarding the position of corresponding temporary defect informationTDFL #i.

As previously explained with reference to FIGS. 4A through 4D, temporarydefect information TDFL #i according to an aspect of the presentinvention is repeatedly recorded several times. Accordingly, theinformation regarding the position of temporary defect information TDFL#i are recorded several times and includes pointers corresponding totemporary defect information TDFL #I. Each pointer points to therecording position of a corresponding copy of the temporary defectinformation TDFL #i. Temporary defect management information TDDS #ishown in FIG. 5A includes P pointers for temporary defect informationTDFL #i recorded P times.

Also, the temporary defect management information TDDS #i recorded on asingle record layer disc 100 such as that shown in FIG. 2A furtherdescribes an address of a last recorded user data, which is lastrecorded in a user data area of a record layer L0, and an address of alast recorded replacement data, which is last recorded in a spare areaof the record layer L0. Accordingly, a user can easily utilize the disc100 just by referring to the last recorded user data and replacementdata.

FIG. 5B illustrates a data structure of temporary defect managementinformation TDDS #i recorded on a double record layer disc 100 such asthat shown in FIG. 2B. Temporary defect management information TDDS #icontains an identifier for temporary defect management information TDDS#i, and information regarding the recording position of correspondingtemporary defect information TDFL #i. As previously mentioned withreference to FIGS. 4A through 4D, temporary defect information TDFL #iaccording to an aspect of the present invention is repeatedly recordedseveral times. Thus, the information regarding the recording position oftemporary defect information TDFL #i which contains pointers pointing tothe recording positions of respective temporary defect information TDFL#i, are recorded several times. In particular, temporary defectmanagement information TDDS #i shown in FIG. 5B includes P pointers.Each pointer points to a corresponding copy of the of the temporarydefect information TDFL #i.

Also, temporary defect management information TDDS #i recorded on adouble record layer disc 100 such as that shown in FIG. 2B furtherdescribes an address of a last recorded user data that is last recordedin a user data area of a first record layer L0, the address of a lastrecorded replacement data that is last recorded in a spare area of thefirst record layer L0, an address of a last recorded user data that islast recorded in a user data area of a second record layer L1, and anaddress of a last recorded replacement data that is last recorded in aspare area of the second record layer L1. Accordingly, a user can easilyutilize the disc 100 just by referring to the last recorded user dataand last recorded replacement.

FIG. 6 illustrates a data structure of temporary defect information TDFL#1 according to an aspect of the invention. Referring to FIG. 6,temporary defect information TDFL #i contains an identifier fortemporary detect information TDFL #i, and information regarding defects#1, #2 nd #K. The information regarding defects #1, #2 nd #K comprisesstate information indicating the positions of the defects and thereplacements, and whether a defective area is a single defect block or acontinuous defect block.

Generally, data can be processed in units of sectors or clusters. Asector denotes a minimum unit of data that can be managed in a filesystem of a computer or in an application. A cluster denotes a minimumunit of data that can be physically recorded on a disc 100 at once. Ingeneral, one or more sectors constitute a cluster.

There are two types of sectors: a physical sector and a logical sector.The physical sector is an area on the disc 100 where a sector of data isto be recorded. An address for detecting the physical sector is called aphysical sector number (PSN). The logical sector is a unit in which datacan be managed in a file system or an application. An address fordetecting the logical sector is called a logical sector number (LSN). Adisc recording/reading apparatus such as that in FIG. 1 detects therecording position of data on the disc using a PSN. In a computer or anapplication relating to data, the entire data is managed in units ofLSNs and the position of data is detected using an LSN. The relationshipbetween an LSN and a PSN is changed by a controller 2 of therecording/reading apparatus, based on whether the disc 100 contains adefect and an initial position of recording data.

Referring to FIG. 7, the disc 100 includes a user data area A and aspare area B in which PSNs are sequentially allocated to a plurality ofsectors (not shown) according to an aspect of the invention. In general,each LSN corresponds to at least one PSN. However, since LSNs areallocated to non-defective areas, including replacements recorded in thespare area B, the correspondence between the PSNs and the LSNs is notmaintained when the disc 100 has a defective area, even if the size of aphysical sector is the same as that of a logical sector.

In the user data area A, user data is recorded either in a continuousrecording mode or a random recording mode. In the continuous recordingmode, user data is recorded sequentially and continuously. In the randomrecording mode, user data is randomly recorded. In the data area A,sections 1001 through 1007 denote predetermined units of data in whichthe verify-after-write method is performed. A recording and/orreproducing apparatus such as that shown in FIG. 1 records user data insection 1001, returns to the start of section 1001, and checks if theuser data is appropriately recorded or a defect exists in section 1001.If a defect is detected in a portion of section 1001, the portion isdesignated as defect #1. The user data recorded in defect #1 is alsorecorded on a portion of the spare area B so as to provide replacementdata for a portion of the user data which was recorded in the defect #1area. Here, the portion of the spare area B in which data recorded indefect #1 is rewritten is called replacement #1. Next, the recordingapparatus records user data in section 1002, returns to the start ofsection 1002, and checks whether the data is properly recorded or adefect exists in section 1002. If a defect is detected in a portion ofsection 1002, the portion is designated as defect #2. Likewise,replacement #2 corresponding to defect #2 is formed in the spare area B.Further, defect #3 and replacement #3 are designated in section 1003 ofthe user data area A and the spare area B, respectively. In section1004, a defect does not occur and a defective area is not designated.

The recording and/or reproducing apparatus records information regardingdefect #1, #2, and #3 occurring in sections 1001 through 1003 astemporary defect information TDFL #0 in a TDMA, when recording operation#0 is expected to end, after the recording and verifying of data tosection 1004 (i.e., when a user presses the eject button of a recordingapparatus or recording of user data allocated in a recording operationis complete). Also, management information for managing temporary defectinformation TDFL #0 is recorded as temporary defect managementinformation TDDS #0 in the TDMA.

When recording operation #1 starts, data is recorded in sections 1005through 1007 and defects #4 and #5 and replacements #4 and #5 are formedin the user data area A and the spare area B, respectively, as explainedin sections 1001 through 1004. Defects #1, #2, #3, and #4 occur in thesingle blocks, whereas defect #5 occurs in is a continuous defect block.Replacement #5 is a continuous replacement block that is replacementdata for the user data recorded in defect #5. According to an aspect ofthe invention, a block refers to a physical or logical record unit, arange of a unit block not being limited. If the second recordingoperation is expected to end, the recording apparatus recordsinformation regarding defects #4 and #5 as temporary defect informationTDFL #1, and records the information contained in the defect informationDFL #1 once again. Thereafter, management information for managingtemporary defect information TDFL #1 is recorded as temporary defectmanagement information #1 in the TDMA.

FIG. 8 is a diagram illustrating effective use of a user data areaaccording to an aspect of the present invention. FIG. 8 shows that anavailable portion of a user data area can easily be detected with anaddress of user data that is last recorded in the user data area A andan address of replacement that is last recorded in the spare area B.Specifically, the available portion can be more easily detected, whenthe user data is recorded from the inner part/outer part of the userdata area A to its outer part/inner part and data, which is replacementdata for a defect occurring in the user data area A, is recorded fromthe outer part/inner part of the spare area to its inner part/outerpart, respectively. In other words, the user data and the replacementdata are preferably recorded in the opposite recording directionsaccording to an aspect of the invention.

For a disc 100 such as that shown in FIG. 2B, when physical addresses ofuser data are increased from the inner part of the first record layer L0to the outer part and increased from the outer part of the second recordlayer L1 to the inner part, a physical address of the last data, whichis last recorded in the corresponding user data areas A of the recordlayers L0 and L1, has the largest number. Also, last recordedreplacement data has a physical address with the smallest number, whenphysical addresses of replacements are reduced from the outer part tothe inner part in the spare area B of the first record layer L0 andincreased from the inner part to the outer part in the spare area B ofthe second record layer L1. Accordingly, as previously mentioned, if theaddresses of the last recorded data and last recorded replacement dataare included in the temporary defect management information TDDS #i, itis possible to detect the positions of data and the replacement datathat are to be newly recorded, without completely reading the temporarydefect information TDFL #i and estimating the positions of the defectand the replacement data. Further, available portions of the user dataarea A and the spare area B are located continuously, thereby enablingeffective use of the user data area A.

FIGS. 9A and 9B illustrate data structures of temporary defectinformation TDFL #0 and TDFL #1 recorded as explained with respect toFIG. 7. FIG. 10 illustrates a data structure of information regardingdefect #i recorded as explained with reference to FIG. 7.

Referring to FIGS. 9A and 9B, temporary defect information TDFL #0contains information regarding defects #1, #2, and #3. The informationregarding defect #1 indicates a position of an area in which the defect#1 exists and a position of an area in which the replacement #1 isrecorded. The information regarding the defect #1 may further includeinformation indicating whether the defect #1 is a continuous defectblock or a single defect block. Likewise, the information regarding thedefect #2 indicates whether the defect #2 is a continuous defect blockor a single defect block, a position of an area in which the defect #2exists and a position of an area in which the replacement #2 isrecorded. The information regarding the defect #3 indicates whether thedefect #3 is a continuous defect block or a single defect block, aposition of an area in which the defect #3 exists, and a position of anarea in which the replacement #3 is recorded.

Temporary defect information TDFL #1 further contains informationregarding the defects #4 and #5 in addition to the information containedin the temporary defect information TDFL #0. More specifically, thetemporary defect information TDFL #1 includes the information regardingthe defect #1, the information regarding the defect #2, the informationregarding the defect #3, the information regarding the defect #4, andthe information regarding the defect #5.

Referring to FIG. 10, the information regarding a defect #i includesstate information indicating whether the defect #i is a continuousdefect block or a single defect block, a pointer pointing to the defect#i, and a pointer pointing to a corresponding replacement #i. When thedefect #i is determined to be in a continuous defect block, the stateinformation further represents whether a pointer for the defect #ipoints to the start or end of the continuous defect block and whether apointer for the replacement #i points to the start or end of areplacement block that replaces the defect #i. When the stateinformation indicates the pointer for defect #i as the start of thecontinuous defect block and the pointer for the replacement #i as thestart of the replacement block, the pointer for the defect #i representsa starting physical sector number of the continuous defect block and thepointer for the replacement #i represent a starting physical sectornumber of the replacement #i.

In contrast, when the state information indicates the pointer for thedefect #i as the end of the continuous defect block and the pointer forthe replacement #i as the end of the replacement block, the pointer forthe defect #i represents an ending physical sector number of thecontinuous defect block and the pointer for the replacement #i representan ending physical sector number of the replacement #i. The definitionof a continuous defect block using state information enables effectivelyrecording of information and saves a space of recording, even ifinformation regarding defects is not recorded in units of blocks.

The pointer for the defect #i specifies a starting point and/or endingpoint of the defect #i. The pointer for the defect #i may include astarting PSN of the defect #1 according to an aspect of the invention.The pointer for the replacement #i specifies a starting and/or endingpoints of the replacement #i. The pointer for the replacement #i mayalso include a starting PSN of replacement #1 according to an aspect ofthe invention.

Hereinafter, a disc defect management method according to embodiments ofthe present invention will be described with reference to theaccompanying drawings with reference to FIGS. 11 and 12.

FIG. 11 is a flowchart illustrating a disc defect management methodaccording to an embodiment of the present invention. In action 1101, arecording apparatus records defect information regarding data, which isrecorded according to a first recording operation, as first temporarydefect information in a TDMA of a disc. This process serves to managedisc defects. In action 1102, the recording apparatus records managementinformation for managing the first temporary defect information as firsttemporary defect management information in the TDMA.

In action 1103, it is checked whether finalization of the disc isrequired. In action 1104, if it is determined in action 1103 that thefinalization of the disc is not required, actions 1101 and 1102 arerepeated while increasing an index given to each recording operation,temporary defect information, and temporary defect managementinformation by 1. However, it is understood that other numbers can beused for the index to the extent that the numbers serve to distinguishsets of recorded data.

If it is determined in action 1103 that finalization of the disc isrequired, a last recorded temporary defect management information and alast recorded temporary defect information are recorded in a DMA (action1105). That is, the last recorded temporary defect managementinformation and the last recorded temporary defect information arerecorded as the final defect management information and defectinformation in the DMA, respectively. The final defect information anddefect management information may be repeatedly recorded to increase thereliability of data detection.

Further, according to an aspect of the invention, the verify-after-writemethod may be performed on the final temporary defect managementinformation and temporary defect information. If a defect is detectedfrom this information, an area of the disc having the defect and thefollowing area containing data may be regarded as being unavailable(i.e., they are designated as a defective area), and the final temporarydefect management information and temporary defect information may beagain recorded after the defective area.

FIG. 12 is a flowchart illustrating a disc defect management methodaccording to another embodiment of the present invention. In action1201, a recording apparatus records user data in a data area of a discin units of data to facilitate the verify-after-write method. In action1202, the data recorded in action 1201 is verified to detect an area ofthe disc having a defect. In action 1203, the controller 2 of FIG. 1designates the area having the defect as a defective area, controls therecording/reading unit 1 to rewrite data recorded in the defective areato a spare area so as to create a replacement area, and creates stateinformation specifying whether the defective area is a single defectblock or a continuous defect block, and pointer information that pointsto the positions of the defective area and the replacement area. Inaction 1204, the state information and the pointer information arestored as first temporary defect information.

In action 1205, it is checked whether the first recording operation isexpected to end. If it is determined in action 1205 that the firstrecording operation is not expected to end, actions 1201 through 1204are repeated. In action 1206, if it is determined in action 1205 thatthe first recording operation is likely to end (i.e., when the recordingof the user data is complete by user input or according to the firstrecording operation), the stored temporary defect information is readand repeatedly recorded as first temporary defect information TDFL #0 ina TDMA several times. In action 1207, management information formanaging the first temporary defect information TDFL #0 is recorded asfirst temporary defect management information TDDS #0 in the TDMA.

In action 1208, it is checked whether the data needs to be finalized. Ifit is determined in action 1208 that finalization of the disc is notrequired, actions 1201 through 1207 are repeated. In action 1209,whenever actions 1201 through 1207 are repeated, an index given to acorresponding recording operation, temporary defect information TDFL,and temporary defect management information TDDS is increased by 1.However, it is understood that other numbers can be used for the indexto the extent that the numbers serve to distinguish sets of recordeddata.

In action 1210, if it is determined in action 1208 that the finalizationof the disc is needed, a last recorded temporary defect information TDFL#i and a last recorded temporary defect management information TDDS #iare recorded as the final defect information DFL and the final defectmanagement information DDS in the DMA. Recording of the final defectinformation DFL and the final defect management information DDS may berepeated several times to increase the reliability of data detection.Similarly, the verify-after-write method may be performed on the finaldefect information and defect management information. If a defect isdetected in this information, an area of the disc having the defect andthe following area containing data may be regarded as being unavailable(i.e., they are designated as a defective area), and the final temporarydefect management information and temporary defect information may beagain recorded after the defective area.

The aforementioned defect management may be embodied as a computerprogram that can be run by a computer, which can be a general or specialpurpose computer. Thus, it is understood that the controller 2 can besuch a computer. Codes and code segments, which constitute the computerprogram, can be easily reasoned by a computer programmer in the art. Theprogram is stored in a computer readable medium readable by thecomputer. When the program is read and run by a computer, the defectmanagement is performed. Here, the computer-readable medium may be amagnetic recording medium, an optical recording medium, a carrier wave,firmware, or other recordable media.

In addition, it is understood that, in order to achieve a recordingcapacity of several dozen gigabytes, the recording and/or reproducingunit 1 could include a low wavelength, high numerical aperture type unitusable to record dozens of gigabytes of data on the disc 100. Examplesof such units include, but are not limited to, those units using lightwavelengths of 405 nm and having numerical apertures of 0.85, thoseunits compatible with Blu-ray discs, and/or those units compatible withAdvanced Optical Discs (AOD).

As described above, the present invention provides a disc defectmanagement method that is applicable to write-once discs. According tothe present invention, at least one temporary defect information area ispresent in a lead-in area of a disc and/or a lead-out area, so thatinformation regarding a defect that exists in the disc can beaccumulatively recorded. Also, it is easy to finalize the disc byreading only lastly recorded temporary defect information from atemporary defect information area and recording the read information ina defect management area, thereby enabling effective use of the DMA.Accordingly, user data can be recorded even on write-once discs whileperforming disc defect management, thereby performing backup operationsmore stably without interruptions.

While described in terms of use with write-once disks, it is understoodthat the present invention can be used with other writeable discs,including re-writeable recording media.

While this invention has been particularly shown and described withreference to preferred embodiments thereof, it will be understood bythose skilled in the art that various changes in form and details may bemade therein without departing from the spirit and scope of theinvention as defined by the accompanying claims and equivalents thereof.

1. A method of accessing data in a disc, the disc comprising a user dataarea and a spare area other than the user data area having replacementdata for user data recorded in a defective area of the user data area,the method comprising: reading temporary defect information andtemporary defect management information in a temporary defect managementarea of the disc, wherein the temporary defect information comprises adefect position pointer that points to the defective area and areplacement position pointer that points to the position of thereplacement data; and accessing the recorded user data based on thetemporary defect information and the temporary defect managementinformation; wherein the temporary defect management informationcomprises position information of the temporary defect information. 2.The method of claim 1, wherein the temporary defect information furthercomprises state information that specifies a state of the defectivearea.
 3. The method of claim 1, wherein the disc is a write-once storagemedium having a property which prevents, after the data is recorded onan area of the disc, new data from being written to the area of thedisc.
 4. A computer-readable medium encoded with computer-executableinstructions implemented by a computer to perform the method of claim 1.5. The method of claim 1, wherein: the disc further comprises a defectmanagement area; the reading comprises reading temporary defectinformation and temporary defect management information in the defectmanagement area and/or the temporary defect management area; and theaccessing comprises accessing the recorded user data based on the readtemporary defect information and the temporary defect managementinformation.
 6. The method of claim 5, wherein: the defect managementarea is empty prior to finalization of the disc, and the readingcomprises: prior to finalization of the disc, reading temporary defectinformation and temporary defect management information from thetemporary defect management area, and after finalization of the disc,reading the temporary defect information and temporary defect managementinformation from the defect management area with the temporary defectinformation and temporary defect management information having beencopied from the temporary defect management area during finalization ofthe disc.
 7. The method of claim 1, wherein the disc further comprises adefect management area which is empty and reserved for recording a copyof the temporary defect information and temporary defect managementinformation from the temporary defect management area.